This tool

[rasmeidirt]

it takes lots of skill to use it.
in a harness, oh boy.
the wires eaCH HAVE capacitance to each other wire,  (do you understand what capacitance does?) and the signals shows up on all wires in a bundle.
so is not very good on bundles of wires, IMO.

but  if you already knew the cable was cut (unseen)
you'd have unwrapped the harness and each wires is laid out  flat separate and the wire with the most load sound is that wire then see if it drops to zero. at cut, hidden deep, in wire.
I have used this VAST Time, and vast ways, homes , businesses and cars  only if desperate and am never.(on cars)

I only need this for in buried deep wires in walls tracking or deep in the ground/
a car never blocks me from gaining access to any wire, ever, and I can test it the normal way. (with any voltmeter)
even using needles is need be.  most times I find the exact section of wire that fails,  like from drivers door to rear of card,  we are talking what here, 5 feet of wire.
then I pull the wire, as I do I see the insulation collapse , BINGO. (mind you the connectors at both ends were inspected and tested for good.)

btw NOTHING NEW HERE,  only FB goons think it is.

Thanks for this. Just curious!

May be you can teach the basics how to find the opened wire or shot.